Oswego is a city in and the county seat of Labette County, Kansas, United States, and situated along the Neosho River. As of the 2020 census, the population of the city was 1,668.

Labette County is a county located in Southeast Kansas. Its county seat is Oswego, and its most populous city is Parsons. As of the 2020 census, the county population was 20,184. The county was named after LaBette creek, the second-largest creek in the county, which runs roughly NNW-SSE from near Parsons to Chetopa. The creek in turn was named after French-Canadian fur trapper Pierre LaBette who had moved to the area, living along the Neosho River, and marrying into the Osage tribe in the 1830s and 1840s.